This invention pertains generally to gas plasma processes and materials and more particularly to a process and gas useful for the removal of materials in the manufacture of semiconductor devices in a plasma environment.
In the treatment of semiconductor devices in a gas plasma environment, the wafers or devices to be treated are commonly placed in a reactor chamber in which a reactant gas is excited with RF energy to form a gaseous plasma to which the wafers or devices are exposed to effect the desired treatment, e.g., etching of a metallization layer, etching of a passivation or diffusion barrier, or stripping of photoresist.
Heretofore, halocarbons such as CF.sub.4 have been utilized in the plasma treatment of semiconductor devices, and one process utilizing a mixture of a halocarbon and oxygen is disclosed in U.S. Pat. No. 3,795,557, dated Mar. 5, 1974. One of the by-products of such reactions is silicon tetrafluoride (SiF.sub.4) which, prior to the invention disclosed herein, was not thought to be of any utility in the processing of semiconductor wafers or other devices containing silicon.